Re: strange bug in plperl - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: strange bug in plperl
Date
Msg-id 40E975A0.30302@dunslane.net
Whole thread Raw
In response to Re: strange bug in plperl  (Darko Prenosil <darko.prenosil@finteh.hr>)
List pgsql-hackers
OK, thanks. I see where the problem is. We'll fix the SRF code.

cheers

andrew


Darko Prenosil wrote:

>Because that is exactly count of "tstset" function being called. Set returning 
>functions are called recursively until SRF_RETURN_DONE is returned, and that 
>in You case means until last row is fetched.
>
>When You programming functions in "C", there is SRF_ISFIRST_CALL function that  
>returns "true" if function is called for the first time, so You can write 
>something like this:
>
>if (SRF_ISFIRST_CALL())
>{
>    //Code that executes only once
>}
>else
>{
>    //Code that executes per row
>}
>
>
>I do not know how this works with plperl, and this could be a bug, because 
>only "return [{i=>1,v=>"one"},{i=>2,v=>"two"}];" should be executed more than 
>once (that is the way it is working in pl/psql). 
>I'm sorry I can't help more, but do not know much about plperl :-(
>Hope some plperl guru will know more...
>
>Regards !
>
>On Monday 05 July 2004 15:33, Andrew Dunstan wrote:
>  
>
>>Can anyone suggest why I might be seeing this effect (each notice comes
>>out once per row plus once per function call)
>>
>>thanks
>>
>>andrew
>>
>>andrew=# create function tstset() returns setof tst language plperl as $$
>>andrew$# elog(NOTICE,"tstset called");
>>andrew$# return [{i=>1,v=>"one"},{i=>2,v=>"two"}];
>>andrew$# $$;
>>CREATE FUNCTION
>>andrew=# select * from tstset();
>>NOTICE:  tstset called
>>NOTICE:  tstset called
>>NOTICE:  tstset called
>> i |  v
>>---+-----
>> 1 | one
>> 2 | two
>>(2 rows)
>>
>>
>>---------------------------(end of broadcast)---------------------------
>>TIP 8: explain analyze is your friend
>>    
>>
>
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>


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